I have an old gryphon 3/4 3 phase motor that I'd like to use on my Taiwanese RF31 with a VFD. Will have to mod the frame to bracket plate and make a 5/8" to 7/8" shim for the shaft but I'm wondering if 3/4HP will be adequate. According to ME consultant the max RPM I need for the work I do is 1/4HP. The original motor is 1.5HP but I doubt it puts out more than 1