yes they will bolt up i have the 700r4 behind my 5.3 i used the hughes flexplate part#hp4004 , ls1 adapter #hp3795 thats all you will need to bolt the turbo 400 it has both bolt patterns for the two converters but the 700r4 will need the bowtie overdrive throttle valve cable kit, just completed the swap, so any questions just hit me up