There is an article on my web page about joining plastic covering. I used this method twice with no problems. Actually, I used it on the first covering job I did with plastic. When I covered, the stabilizer, I overheated with the heatgun and it pulled apart but I avoided doing that again and completed the rest of the plane without incident. I did not use monocoat but used Sig Supercoat but I assume that all of them would work basically the same.