youcan use the 2.9L monts, they bolt in.
if you use the 2.9L flywheel then you will need to use the starter from an automatic 4.0L which if you have a complete automatic aerostar then the starter will work for what you will be using. I will recomend that you use the 4.0L flywheel for better transfer of torque but I ran the 2.9L because of the tranny not being rated to handle the motor. clutches are cheaper then tranny's.
the van manifolds will work but you will need to notch the passengerside motor mount to clear.....you will see what I am talking about when you go to assemble. you will have to make your own y pipe for the exhaust.
the other thing you need to be aware of is the oil filter pickup......if you use the one from the aerostar you will have to clearence the bell housing to fit the FL1A oil filter, or switch to a FL400S (both motor craft numbers, fram is PH8A or PH3600) I just used the 400S and called it good. but it is personal preference. if you decide to use the other pickup then you might need to run the other manifolds because of clearence issues. I didn't try this but you might be able to use the 2.9L pickup because they are from the same block family they might interchange.
the exhaust maifolds from the 2.9L will physicly bolt on but if you look at the 2 manifols the port diameter is way different. if you grind to port match you will crack the manifold from the heat transfer of the metal. at this point you have options to run the factory junk from the aerostar, run exploder maifolds, or get headers.
Is the 2.8 the same size as the 4.0???
71 Bronco - twin sticked, full width, 2" lift, wristed arm, lots of rust...
http://www.catalystcycles.com
http://www.catalystcycles.com
ok, i'll stick with the aerostar manifolds for the exhaust.... building a custom Y pipe is no problem since that is what i do for a living.... grinding the mount is no problem either... i have the 4.0 automatic starter, and the 2.9 just had a new flywheel and clutch kit installed before it drove to california and puked... on the oil filter you must be talking about the filter adaptor or mount... the pickup is in the oil pan and connects to the oil pump. i think i saw a ph8a filter when i was looking under the van today. good to know i can use the ph3600 also. what did you do on the front for accesories? the 4.0 has a serpentine belt and the 2.9 has v-belts... i want to retain the a/c on the bronco and would prefere the serpentine if it's not a big hassle. what kind of difference can i expect between the 2.9 and 4.0 in power and economy? the 2.9 in my 86 bronc gets around 23 mpg on the hiway
yeah, I call the filter mount the pickup for some reason....just always have. sorry didn't mean to confuse you. honestly I don't know how you will make the A/C work I just hooked up OBA with mine so I didn't need to adapt the lines......but you might be able to just use everything from a ranger. I did like the 4.0L belt setup better. less to carry incase of failure and easier to switch out acc. on the front of the motor. I noticed a little difference in gas milage but it was mainly from a lead foot I think. my 2.9L NEVER got the number you are posting so you must have gotten lucky and the motor was built on a wed. afternoon. even though you will do a little worse you will like the added power. 

71 Bronco - twin sticked, full width, 2" lift, wristed arm, lots of rust...
http://www.catalystcycles.com
http://www.catalystcycles.com
my 86 has been the best ford i've ever owned.... it's always gotten amazing milage and never really been hurting for power.... when we go on an outing the bronco uses about half the fuel that my buddy uses in his cherokee.....
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