Understand that your engine MUST be in good working order.  Fuel injection replaces the Carbs/Distributor, it does not make an engine in poor condition run better.  The most important things are: 

Compression:  Most EFI installs that had trouble were due to low/no compression on 1 more cylinders.  PERFORM A  COMPRESSION CHECK.  A minimum of 90 psi per cylinder on all cylinders is required. If your engine has poor compression, find out why, repair it and then install the kit.  Poor compression/cylinder misfire will cause major fluctuations in the MAP sensor, which will, in turn, send the wrong amount of fuel to the injectors and make your engine run lousy.

SKILLS:  Do you have the skills to install this?  You need a medium set of mechanical skills to install this kit.  You do not have to be an ace mechanic, but it helps if you have trouble.  The most import tools are a laptop and a voltage meter.  This will allow you and us (remotely) diagnosis lose/disconnected cables, etc.   If you don’t have the skills, I’m am sure someone in your club/locally does for not very much money if any. 

Configuration:  If you plan to use A/C, you must have your Harmonic Balancer modified with a special crank trigger wheel.  We will modify the wheel for a small fee, but you must pay for the shipping to us and return.  Also the A/C compressor will interfere with the Smart DIS coil and the Corvair distributor with logic coil is recommended.  You may have to extend the wiring harness to accommodate your plans.  Use of the 140 engine will also interfere with the placement of the Smart DIS coil pack and the Corvair distributor with logic coil is recommended.