Seems like this info should be easier to find, but, i cant find it.
Anyway.
I have a highboy. It has a 300 in it. I have a 390 in a 2wd f250.
What do i need to use this 390 in place of 300? I know the 2wd perches wont work.
Do i need different frame mounts, or will the 300 mounts work if moved? Will i need a different rubber mount on the block or are they all the same?

Oil pans. I know there is a 4wd fe pan and rear pickup. I dont have one. Will the 2wd pan clear the crossmember? The cross member has been..clearanced for the 300, which is a 78 engine, presumably from a 2wd truck.

 

you will need different frame mounts, 4wd oil pan and a different bell houseing as well. I assume the 300 is bolted up to a manual trans correct?

the FE360/390 was offered in 73-76 for sure in a 4wd. you will also need a different radiator.

2wd perches wont work.

 

I believe i found a set of frame mounts.
Should have everything else covered, as the 390 is in my 73 f250 that is the donor vehicle.
Except for that rediculously overpriced oil pan. Ill use the 2wd pan for now and cross that bridge when i come to it

 

what year hiboy is this going into? I had a 73 hiboy with a 300-6 and later a 390 backed to an np435.

I actually regret going with the 390 and should have stayed with the 300. granted my 390 was very stock though.

 

Highboy is a 76.
It has an np435, so my current bell housing will work.
Ive completely rebuilt my 73 2wd f250, other than body and paint.
The 390 in it is about what a 390gt would be. Whole truck has like 6k miles on it. Always wanted a highboy. So here is my chance. Using all sheetmetal, interior, and engine. Highboy is 44hd, np245, np 205, abd a limited slip dana 61. Geared 4.09/4.10. Rear leafs were shot. Replacing those with earlier f250 spring pack with 10 leafs. And hangers from same truck. Other than that, the highboy bones are good.
Pic is donor truck pulling donor reciever.

 

cool, thanks for the picture