As to the huge mistake of a non removable pump....
I put a union maybe 16 inches above the pump, so the entire pump with plumbing in removable. On the pump side of the union, I put a hose barb, then a short piece of PVC hose to connect the pump to the plumbing. This makes it so if there is any pump vibration, your entire plumbing doesn't vibrate (because of the short piece of flexable tube). Then, if I want to remove the pump, I unscrew the union, and can take the 1/2union-hosebarb-flexible PVC-pump assembly out, and easily put it on the table for maintenance, etc.
if that makes sense...
Oh, and I guess this isn't for an external pump, but internal. I just have it sitting in my sump return tank. Not sure what your plan is.
rob