Once you get to that point it's not much work to remove the rest of the dash and replace the core the proper way. If you're not replacing the AC evaporator core, then you don't need to disconnect the lines through the firewall. You should be able to just pull the HVAC box back a couple inches in order to replace just the core.
His:'00 WJ, 4.7 Limited, stock
Daily Driver: '05 SRT4, Stock turbo, 252 WHP, 321 WTQ
Hers: '03 WJ, 4.7 V8, Kolak Exhaust, IRO 3", Bilsteins, JKS TB, KOR TB Bushings, 32" Cooper ATP's