A good come-along is one of the class of tools one may seldom ever really need......but when you need one, having a really good one is a seriously important safety issue.
The ones I use are a 'Tirfor', also sold as 'Griphoist' 'TU-17, which is rated at 1 ton, and a Chisholm-Moore chain/ratchet type, rated 3/4 ton. The Tirfor works well, but is a bit 'counter-intuitive' to use......you can see the technique in a video on the Youtube programme.
(the Tirfor come-alongs are too expensive to be a good investment, unless you really need its 'length of travel' capability. We 'got lucky' some twenty-ish years ago, getting a new unused one in a surplus lot of comms antenna rigging equipment, at scrap value.......we got the C-M ratchet unit at our local flea market for....if I remember correctly.....a $10......its much easier to use, conveniently light and handy, and has been a very cost-effective investment)
cheers
Carla