The 901 transaxle in a 914 is basically the same as the 901 in an early 911 but as posted, with a flipped final drive ring gear due to the 914's mid engine mounting. Most of the 914, 901 transaxles also have a side shifter nosecone which will require a 911,901 straight shift nosecone.
Flipping the ring gear actually requires more than just unbolting and re-bolting the ring gear from one side to the other. To make the transaxle live after flipping, the ring gear requires precise measurements be taken on lash and depth.
Sometimes it's a lot cheaper to sell the 901 914 transaxle and buy an early or late Porsche 911 transaxle such as a 901 with weak first gear and with 1st gear out of the traditional 5 speed pattern or, a 915 transaxle with the traditional 5 speed pattern and a much stronger 1st gear.