Lux + Towing and Rim Change

[nerdsmakegraves]

Hi! So i have a question that the dealership couldn't answer today and was hoping someone here could help me. I am looking at the GX 550 Lux + since it will be my daily driver and to use it to tow a 2 horse aluminum bumper pull (one horse ONLY). Horse (1500 lbs) with trailer (curb wt 3300 lbs) and gear (highballing 1000 lbs) I'll be at 6000 lbs. Looks like they down graded the Lux + bc of the rims down to 7600 lbs where the Overtrail + is still at 9000 lbs. My question is this...if i just take off the stock 22" that the Lux + comes with and use the stock 18" that come with the Overtrail+ I should be able to add some towing capacity back to around 8000 lbs? I know it will never be the 9000 lbs. The dealership didn't see anything else that would change the towing capacity much bwt the two outside the rims. . I did wish the Lux + also has the downhill assist, crawl assist available as well but i am staying with a 3-5 of my home to trailer and not looking to do long distance so mostly highway and should be ok. Any insight is greatly appreciated, thanks!