It gets worse.
Need a open drive shaft in a length that will fit.
Need to determine the rear axle ratio that will work well with the T5.
If you have a stock front straight axle it will have 6 lug spindles. You will want a rear axle that is 6 lugs which means a truck rear axle (or carry 2 spares).
Starting 1955 second series, the rear axle is wider than your truck which could cause the rear wheels to rub the fenders.
Attaching leaf spring saddles to your donor axle.
Reworking the emergency brake cables.

There are solutions but don't depend solely on what others think or tell you what you need to do. You won't be happy with the results.
Start searching this forum for what others have done in the past. Learn from their mistakes. Study and do research.

I like to use the "Advanced Forum Search". I just now typed-in "rear axle width". It came up with several pages.
One of them is:
https://www.stovebolt.com/ubbthreads/ubbthreads.php/ubb/showflat/Number/948718
We are more that glad to teach anyone who wants to learn how to use the search function.

"Adding CFM to a truck will only help at engine speeds you don't want to use."
"I found there was nothing to gain beyond 400 CFM."