Hitachi ex 300lc3 hydralic pump repair hpv 145

Just curious if anyone has successfully taken apart and repaired any hpv 145 pumps ? I have all the manuals and parts diagrams. It looks like there is many parts to press out. Currently the pumps seem strong but I believe the seals are leaking and have already ordered them. After reading other posts I understand that the bearings could be bad causing the seals to leak. After viewing the parts the seals are an easy part to replace but bearings would require opening up pump and pressing apart. If I do this I would like to find out what parts would be wise to check for most wear and replace while inside. Thanks for any help.