340 in early abody

have been rounding up parts for a /6 to 340 swap in a 65 Valiant, Disk brake k frame off of a 66 formula S, buckets, console,340, 8 3/4, early 70’s 904 ect.. have a few questions for those that have done this, have heard of people running a manual valve body with a floor shifter because it’s hard to get the kickdown right in these swaps, was wondering if that’s true and if so is a manual VB a pain,
also any special oil pan or will any V8 abody pan work
And does anyone know if there a issues with the hood closing on a early A with a V8 and a performer rpm? Thanks all