Reason for the question" one lineset is "buried" in the house framing. and would be ***** to replace. Don't figure would need to up the "tonnage" since all work well now cooling wise. From what I've red very different refrigerant is now standard.
Somebody needs to measure ids of suction and liquid lines. Are they correct for the new system or what compensation may be needed.
Length of lines....at least a carefully measured estimate of length. (Needed to adjust overall assembled system charge properly.).
Get the manuals for the ac unit and evap coil to determine.
Pressure test above max indicated operating pressure for the lines (only) before anything else above is done. If the lines fail, now is the time to find out before new system is attached to them.
Then flush them if above checks shows usable before connecting equipment on each end of them.