Im good with a wrench or welder but Im not able to make a tank. Id love to but its over my pay grade currently
Well, making your own tank may not be the option then, how about having a custom one made by a welding shop? Maybe a place that makes fuel cells for race cars. Although I'm not sure if emissions regulations will play nicely with a custom tank where you live?
I have two 80s with custom-made tanks. One holds 27 gallons and the other 32 gallons. No problem with either but I dont have any sort of regulations or institution to bother me about it.