Quicktime makes a bellhousing to do a t-5 behind a 460you can use a standard regular bellhousing for a toploader and then bolt on an adapter plate to make thebolt pattern and input shaft length work out.
there are only two T-5 transmissions that have the proper spine length and shaft diameter. because there were a zillion more that were in 4 cylinder and 6 cylinder applications and the input shaft is different.
even the better ones will split in two behind a 460.
the other major set-up thing is how to operate the clutch fork.
mcleod makes now a three piece bellhousing that has the rear face plate that has the proper bolt pattern on it.