The drop-in unit, already modified by Langdon, is a good deal for those people who don't have the experience and shop facilities to do the work themselves. Personally, I'd choose to acquire a used item from Ebay or a salvage yard and save a few bucks, but I realize my situation with 50+ years of experience and a shop full of equipment doesn't fit the norm for most of the members of the Stovebolt community. Different strokes for different folks!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!