Gsmoon 150 issues and questions

[BEEFKING69]

Picked this up for 100 bucks the other night and finally figured out what it is and still not much luck with parts finding but i got it running and it seems to run smooth but it takes forever to idle down and although it seems fairly spunky in the mid rpms it has absolutely no climbing power and it seems as if its got more low end in fwd than reverse. For instance i took it through some trails lastnight and in the muddy sections the motor would bogg down and would barley spin the tires as it crawled through where as any of the past 150s would spin the tires and sling mud the whole way through. Wouldn't even spin the tires period in reverse.

Now on hard pack it would run 38 which is plenty as im not the one that will be driving it the most but something has to be done about the low end and id like some suggestions on what to do.

It has the 2 bolt valve cover so will the A12 cam work?
12 grams sliders?
1500 rpm clutch springs and maybe yellow torque spring?