I have had my machine for several years and have cleaned it regularly removing the group assembly valve. Today the group assembly valve came apart when I was I was taking it out and only the spring and pea came out. The main part of the valve is still in there. I believe I took it out lefty loosely. Should I have taken it our righty tighty thereby leaving the pea and spring in.. In the past they have come out as a unit and I have taken the spring valve out by using a vice grip and a ratchet. I completed the cleaning and descaling of my machine and it is still running very slow with the coffee coming out at an excruciatingly slow pace.

Doesn't really matter. On my Gaggias whenever I replaced this valve I only replaced the pea and spring, not the valve housing.

You probably need a new valve. Try removing the pea/spring, stretch the spring by hand a bit, reassemble, and see if the coffee is any better. If so, order a replacement (the 'stretch' fix is not permanent).