ENGINE INSTALLATION INSTRUCTIONS PART NO 3941193 CONT GENERAL INFORMATION CONT 2 When using on powerglide installation remove clutch pilot bearing 3 The intake manifold of this engine has a plugged 3 B tapped hole on the runner as a source of vacuum for power brakes If desired this source can be utilized on past models by purchasing and installing the following parts a 1 3817691 hose support mount with existing rocker cover screw b 1 3829031 elbow 3 8 c 2 3829058 hose clamp d AR 3830662 11 32 I D hose IMPORTANT When converting to the above vacuum source plug previous source of vacuum with suitable pipe plug 4 Models with optional equipment require transfer or replacement of engine parts special to such options 5 If any part number listed above is not shown in the current Master Parts Catalog check history section of the catalog for replacing part number 6 It may also be necessary to relocate the accelerator pull back spring bracket in order to obtain proper tension 7 The intake manifold of this assembly is manufactured to accept the Rochester Carburetor only lt is necessary to make Item R change for Holley or Carter Carburetor 197O CHEVROLET MOTOR DIVISION GENERAL MOTORS CORPORATION P A 30 34