I use the browser version, Not exe.
Im sure you saw my prior reply detailing how moving the shop is temporary because it will disappear at the end of the day, and will always respawn at the acre's designated point (iirc, I have no means to test this atm. If anyone else has information that would be awesome)
Anyway, if you still want to try, or if you want to move the tree right 3 and down 3 to get a similar effect, there is a tab for buildings and pwp in the web editor. You can adjust coordinates here. Add or subtract whatever you need, or use the map page to find the exact coordinates you want. If redd's shop is currently in the town when you extract the garden.dat or acrambin it will appear here on the buildings page. You may have to scroll down to find it.
If you successfully move it, you can time travel to the next day to see if it stays there. You can also check various days to see if this will affect katrina and gracie's spawn points. I dont think it does, but I could be wrong. If you do this testing, please share your results so we can help anyone else with these questions in the future