I would replace our current RV cooktop/oven "toy" with a REAL freestanding range (like an Insignia) in a heartbeat... but for me in our class C, far too many mods are needed. For REAL cooking/baking - nothing beats the even heat and temperature control you get with a decent sized gas range/oven. Induction wins in efficiency, but I'll take the versatility of gas/propane any day.
The bonus is I love to cook on the road, which is fortunate, because restaurants have become just TOO expensive for my blood!
Your "Thor certified installer" (??) just needs to do detailed measurements of the area where you'll be installing. Also consider sidewall insulation from the oven heat, and roof ventilation (range hood). This is really no different a procedure than you'd do for a home oven/range installation. Any qualified installer should know exactly how to go about this.
After you get the measurements, start shopping. I replaced our ancient 30 year old home wall oven last year using this exact method. Nearly every range/oven has installation spec. and install guide on the internet. Just do a search.
Good luck!