I've read a few posts that suggest it's possible to replace the stock carburetor on my '78 Honda Express with a more reliable carb. I have an intake adaptor (19mm), so theoretically I can mount a new PHBG carb, such as Dellorto's. But there seem to be a lot of options for size/style depending on what kind of performance one wants. I don't need more speed, just something that's more reliable and easier to keep tuned. Basically just a replacement, as close as possible to the original. Any suggestions for which carb would be a good choice? Also, can I just replace the carburetor for now without messing with the exhaust or oil pump? Thanks!