Bill, I spoke with Eagle this morning and we looked at your PI slimlines and note that you seem to be using two different kits. If your slimline kits are from two different manufacturers, there is a small difference in the tubes (PSI kits are typically a little smaller, in my experience). The transmissions are also a hair smaller. Have you measured the components to be sure you have an 8mm tube? You may just have mismatched parts which could be disassembled and reassembled. You can even test fit a transmission in the upper barrel, since that part is easily removed.