HBG and BG in the same pond is not the best idea. I would not add the HBG.
There are different options on adding LMB. If you wait until fall then use larger advanced fingerling LMB (6 inch +) and use only about 35. If you decide on June then use 2 inch and use 75+-. You want the first spawn of BG and RES to not be decimated by the LMB. Initial stocking #s for BG/RES using 2-3 inch fish range from 1000 to 3000 per acre depending on goals. This changes if you use advanced size BG/RES and they spawn quickly without LMB present.