i don't think they're close. old non vtec v6's (the 2.7 in the 1st gen legend/5th gen accord and 3.2 in 2nd gen legend/1st gen TL)
were mounted longitudinally mounted. the new vtec v6's (tl, cl, accord) are mounted sideways. maybe u could ask a mechanic?

also, the 5th gen v6 front end was like 3-4 inches longer than the i4 front end.