Hey Joe, well we all know shop labor prices aren't cheap lol. If your having them do the whole project I doubt they'd appreciate or allow you to shop lower prices on individual parts and pieces. If you only have 1 referred/reputable shop then pretty much what they quote is what it is.
The reason I mentioned HP is because you didn't mention what rear you had in the car, posi, gear set? Depending on the converter they selected you want to make sure your getting the best cruising experience.
Check out your local car scene, shows, cruise in's, drag strips (I know your not racing it but car guys are car guys) and ask questions.
I don't want to get into your personal business, but you could save a ton of money doing it yourself. Plus you'll get all the swearing/bleeding/knuckle busting experience that goes with it. There are a ton of knowledgable people on this site that have pretty much done everything to help you out along the way. The only hurdle would be getting a friend or two to help you pull the old and drop the new motor in the Monte.