It depends on the time of measurement, but presuming you mean when they arrived on the field before taking any casualties, Busey and Martin's Regimental Strengths and Losses at Gettysburg show their engaged strenth (that is, excluding non-combatants) as:
16 GA: 31 officers, 272 enlisted men
18 GA: 30 officers, 272 enlisted men
24 GA: 31 officers, 272 enlisted men
Cobb's Legion: 22 officers, 191 enlisted men
Phillips' Legion: 28 officers, 245 enlisted men
3 BN SS: 21 officers, 208 enlisted men
As the odds of the first three regiments being of equal strength are unlikely, it would appear that an average was adopted, but it does not matter for the purpose of calculating the brigade front. Now, I use my own "rule of thumb" as 22 inches per enlisted man (rather than "by the book" width of 20 inches per man), which seems to fit rather well in cases where units are posted along a known front. I only count the enlisted men in my simple system (I don't bother excluding the sergeant major on the regimental staff), and in this case we exclude 3 BN SS since they acted as skirmishers. So, with two equal ranks, I come up with:
16 GA: 249 feet (272 times 22 inches, divided by 12 inches per foot, divided by 2 ranks)
18 GA: 249 feet
24 GA: 249 feet
Cobb's Legion: 175 feet
Phillips' Legion: 225 feet
Total:
1,147 feet
Sometimes, a participant records (in official reports, regimental histories, etc.) the number of "guns" present which is nearly always the most accurate figure to use, but I'm unaware of such information being available for regiments of Wofford's brigade.
Wofford's brigade came under artillery fire initially, and as
@lelliott19 has shown, a very damaging single artillery round struck 16 GA early on, so the above numbers start shrinking as men close gaps left by casualties. Usually we can get some sense of the attrition by studying casualties by type (gunshot, artillery, bayonet, etc.), to include captures, but unfortunately there are few extant sources from Wofford's brigade to assist such analysis, and even their service records are sketchy.
We can derive an estimate of battle strength and frontage at the end of the fight, too, again mainly relying on Busey and Martin:
16 GA: 130 enlisted men (119 feet)
18 GA: 228 enlisted men (209 feet)
24 GA: 186 enlisted men (170 feet)
Cobb's Legion: 153 enlisted men (140 feet)
Phillips' Legion: 178 enlisted men (163 feet)
Total:
801 feet
Of course, the latter represents a very general estimate. After a large battle, men were often away tending to the wounded, or their own minor wounds (which might not be officially counted as wounds), and sometimes a number of detailed non-combatants would be placed back into the ranks.