Originally Posted by Erick561

New info. I'm close to putting my 79 cab on my 88 frame. Threw this together this afternoon.
The 84 and 85 front cross member is 1.46 inches higher than the middle of the frame; The 86-95 front xmember is flush with the middle
1st gen Cab mount width eye to eye

• Front 31.5 inches
• Middle 47.16 inches
• Rear 47.56 inches

2nd gen Width eye to eye

• Front 33.07 inches
• mid 46.3 inches
• rear 46.3 inches

1st gen Length, eye to eye

• Between 1st and 2nd body mount, 44.61 inches
• Between 2nd and 3rd body mount, 38.5 inches
• Overall length of cab mount front to rear, 83.11 inches total

2nd gen Length, eye to eye

• Between 1st and 2nd body mount, 43.98 inches
• Between 2nd and 3rd body mount, 43.78 inches
• Overall length of cab mount front to rear, 87.76 inches total

Width Difference between 1st and 2nd gen
Relocating body mounts to fit 1st gen cab on 2nd gen frame

• Move Front Cab mount .785 inches inward on each side.

I think that the height will be lower than the 79-83 frame if you're working with an 86-88 frame because the crossmember is 1.46 inches higher on a SFA frame, not 100% sure on that though.

• Middle cab mounts will have to be moved .515 inches outward on both sides and .63 inches back on each side.
  
• Rear cab mounts will have to be moved 4.65 inches forward, and .63 inches outward.

Originally Posted by Erick561

4 out of 6 cab mounts are in now. I do not have any pictures at this time but I will have them soon. Again, change of plans, instead of using the cab to bolt the cab mounts to and sliding the frame under it to tack them in place, we used math. Oh do I love math :laughing:
The front cab mounts were cut flush across the bend to measure 2 1/8" from center eye to the bend. Tacked in place, they were 2"s from the outside of the frame rail to make a total of just under 31 1/2"s (I measured eye to eye on my 1st gen cab and it wasn't quite accurate with the dimensions I've found on the internet). This will make for a lower stance on my truck due to the fact that the 1st gen frame has 1.46" more lift than IFS frames and I did not use the 1st gen cab mounts.

I salvaged the middle cab mounts from the 1st gen frame. Before cutting them out, the measurement eye to eye from the front mount to the middle mount eye to eye was 46 1/8 inches; this was easier to measure than moving the mounts to a right angle measurement, as provided by the dimensions found in the FAQ. These measurements were duplicated best as possible, but we're surely doing this the hard way! My dad is one of the best fabricators in New England, though, so this is a cinch for him, and Pirate has been an encyclopedia for me

The rear cab mounts were made custom by my father and I installed and them in.



They will not be factory dimension so they're going in last, once the cab is lowered onto the frame for a test fit.

I plan on having my cab ready for paint and bed liner by the end of next week. :beer: