any H series pam will most likely be a sandwich dial, afaik.. as for as mods goes..its entirely individual preference on what flaw u can live with&what u cant..
just a list of mods, if u'r considering a full mod but not franken status:-
1. CG - either a Toro or LH & i think wholesale outlet's CG isnt too bad either-
2. Crown - T's & e Palp crown are e best, i think but hard to source, OEM is e next option..
3. AR - either remove e AR coating on e rep crystal or go to either finedd or taka for an aftermarket crystal depending on where u r.
4. Lume - again afew modders to chose frm depending on ur location.. goin, ziggy, vac, etc etc.. as for combination & mixture of which lume to be as per gen both in day&night conditions, idk..
5. Dial - DSN's 111H&112H dials are pretty accurate, i think.. but there's LH or even OEM if u'r able to source for them..
6. Movement - depending on how the text looks like on e movement.. u can either go e francisco direction or LH for a fully serviced, engraved movement.. not too sure who or where else u can source a engraved movement..
7. Case - its smth not everyone will consider as e rep cases are pretty good. but if u really wana be nitpicky, then sourcing a OEM is e best option i guess..
8. Strap - a must have but not exactly a mod, imho.. great variety, choices, makers, styles, etc etc to chose frm..
i guess tts about it.? hahahaha.. enjoy the poison