The 2nd Tactical Air Force Typhoon units at 6th June 1944 were:
From 83 Group:
121 Wing based at Holmesley South, made up of
174 Squadron (RPs) (codes XP)
175 Squadron (RPs) (codes HH) and
245 Squadron (RPs) (codes MR);
124 Wing based at Hurn, made up of
181 Squadron (RPs) (codes EL)
182 Squadron (RPs) (codes XM) and
247 Squadron (RPs) (codes ZY)
129 Wing based at Westhampnett, made up of
184 Squadron (RPs) (codes BR)
143 Wing based at Funtingdon and Hurn, made up of
438 Squadron RCAF (bombs) (codes F3)
439 Squadron RCAF (bombs) (codes 5V) and
440 Squadron RCAF (bombs) (codes I8)
From 84 Group:
123 Wing based at Fundington, made up of
198 Squadron (RPs) (codes TP) and
609 Squadron (RPs) (codes PR)
136 Wing based at Thorney Island, made up of
164 Squadron (RPs) (codes FJ) and
183 Squadron (RPs) (codes HF)
146 Wing based at Needs Oar Point, made up of
193 Squadron (bombs) (codes DP)
197 Squadron (bombs) (codes OV)
257 Squadron (bombs) (codes FM) and
266 Squadron (bombs) (codes ZH)
I've indicated what the main weapons being used by the unit at the time was (rockets or bombs), although some units did use both.
The 'cab rank' fighter-bomber system would mean that there weren't specific squadrons assigned to support any particular ground unit, so you could pick your favourite squadron or code letter.