You can swap the hammer spring for the 16J version (shorter) and replace the transfer port, that's it.
If you replace the regulator of the HP version (120bar) for a FT16J version (85 bar) you will get an incredible shot count as well.
All inclusive in parts it is below 100 Euros (regulator, spring, transfer port) and can easliy be done by yourself.
After that I guess you also need to move the topic then to another section of the forum, long range with 7,5J