I didn't cut my cowl at all, except to make a hole for the needle adjuster to stick out on one side, and a small hole on the other so I could adjust the idle, and i did have to make a relief cutout for the exhaust header.

It's a snug fit, and I had to put my throttle linkage in after the engine is mounted. I used the supplied rod and bent the end in a half loop with a clevis on the end, so the clevis attaches from the front of the throttle arm to give it enough clearance.

I don't know if others with Rascal 40's have had this problem, but I'm betting that anyone with high time on theirs does--- the small aluminum brackets that you mount the engine to, and then screw to the wood rails, eventually break from vibration at one or another screw hole. I made a set from the same thickness of steel, and have had no further problems. There's not enough weight involved with them to change the c/g much, that you can't adjust by moving the battery or Rx.

Yes. mine is inverted, and no, it doesn't have on-board glow, doesn't need it, runs great. The glow plug IS kind of aggravating to get to, though, you might consider a remote plug for convenience.